|
}}
'''Intel 8008''' един от първите [[микропроцесор]]и разработен от[[Intel]] и пуснат на пазара през Април 1972 година. Кодовото му название е ''1201''. Чипът е поръчан от [[Computer Terminal Corporation]] за да въведе нов набор от иструкции за техния програмируем терминал [[Datapoint 2200]]. С забавянето на чипа той не отговаря на изискванията за производителност на CTC's и [[Datapoint 2200|2200]] в крайна сметка изпозва CPU на CTC базиран на [[Транзисторно-транзисторна логика]] (TTL). Intel постигат споразумение да продават чипа на пазара.
Разработен по 10μm silicon-gate enhancement load [[PMOS логика|PMOS]], първите версии 8008 работят с тактова честота 0.5 MHz, по късно увеличена в 8008-1 до 0.8 MHz. Инструкциите се изпълняват между 3 и 11 : register-register loads and ALU operations took 5T (10μs at 0.5 MHz), register-memory 8T (16μs), while (taken) calls and jumps took 11 cycles (22μs). The 8008 was a little slower in terms of [[instructions per second]] (45,000 to 100,000) [http://www.cpu-world.com/CPUs/8008/index.html] than the 4-bit [[Intel 4004]] and [[Intel 4040]], but the fact that the 8008 processed data eight bits at a time and could access significantly more RAM actually gave it 3 to 4 times the true processing power of the 4-bit chips.
The subsequent Intel 8080 and 8085 CPUs were also heavily based on the same basic design; even the [[x86]] architecture (originally a non-strict extension of the [[8085]]) loosely resembles the original Datapoint 2200 design (every instruction of the 8008's instruction set has a direct equivalent in the 8080's larger instruction set and [[Intel Core 2]]'s even larger instruction set, although the opcode values are different in all three).
The chip (limited by its 18 pin [[dual in-line package|DIP]] packaging) had a single 8-bit bus and required a significant amount of external support logic. For example, the 14-bit address, which could access "16 K x 8 bits of memory"<ref name="MCS8">{{cite web|url=http://www.classiccmp.org/8008/8008UM.pdf MCS-8 User Manual|title=MCS-8 Users Manual|format=pdf}}</ref>, needed to be latched by some of this logic into an external Memory Address Register (MAR). The 8008 could access 8 input ports and 24 output ports.
For controller and [[Computer terminal|CRT terminal]] use this was an acceptable design, but it was too difficult to use for most other tasks. A few early computer designs were based on it, but most would use the later and greatly improved [[Intel 8080]] instead.
The 8008 family is also referred to as the ''MCS-8''.
== Designers ==
*'''CTC''' (''Instruction set and architecture''): [[Victor Poor]] and [[Harry Pyle]].
*'''Intel''' (''Implementation in silicon''):
** [[Marcian Hoff|Marcian "Ted" Hoff]] and [[Stan Mazor]] and Larry Potter (IBM Chief Scientist of IBM) proposed a single-chip implementation of the CTC architecture, using RAM register memory rather than shift register memory, and also added a few instructions and interrupt facility
** [[Federico Faggin]] become leader of the project from January 1971, after it had been suspended for about 7 months, until its successful completion in April 1972
** [[Hal Feeney]] project engineer did the detailed logic design, circuit design, and physical layout under Faggin's supervision, employing the same design methodology Faggin originally developed for the Intel 4004 microprocessor and utilizing the circuits of the 4004.
==External links==
* [http://www.classiccmp.org/8008/8008UM.pdf MCS-8 User Manual] with 8008 data sheet (1972)
==References==
{{reflist}}
[[Категория:Компютърен хардуер]]
| 